Agbr - Tio < Sub > 2 < / Sub > Composite Building And Photocatalytic Properties Of Nanomaterials Research

In recent years there has been widespread interest in the development ofAgBr-TiO₂composite nanomaterial. In this study, new microemulsion-like chemicalprecipitation method and phosphorus-oxygen-bridged method have been developed inorder to solve the problem of poorly-contacted between AgBr and TiO₂. Themechanisms of enhanced photocatalytic activity in the as-constructed AgBr-TiO₂nanoheterostructured composite have not been clearly revealed. Surface photovoltagespectroscopy has been used to explore transmission and separation of thephotogenerated charges and then mechanisms of enhanced photocatalytic activity havebeen deeply penetrated. The results are as follows:Simple microemulsion-like chemical precipitation method has been developed toconstruct effectively-contacted AgBr-TiO₂nanoheterostructured composite. The key ofmicroemulsion-like chemical precipitation method is the dual roles of Br-in thesynthetic process. Compared with the AgBr-TiO₂composite which is prepared by thetransitional chemical precipitation method in the water system, the as-constructedAgBr-TiO₂nanoheterostructured composite exhibits enhanced photocatalytic activity.The results of steady-state surface photovoltage spectroscopy and transient surfacephotovoltage spectroscopy show that the enhanced photocatalytic activity is attributedto its effectively-contacted between AgBr and TiO₂which are responsible for goodsituation of transfer and separation of photogenerated charges, and effective capture ofphotogenerated holes of Br-. Meanwhile, microemulsion-like chemical precipitationmethod has also been developed to fabricate effectively-contacted BiOBr-TiO₂nanoheterostructured composite.The new phosphorus-oxygen-bridged method has been developed to constructeffectively-contacted AgBr-TiO₂nanoheterostructured composite. The key ofphosphorus-oxygen-bridged method is the bridged role of phosphorus-oxygen in thesynthetic process. Compared with the AgBr-TiO₂composite which is prepared by thetransitional chemical precipitation method in the water system, the as-constructed AgBr-TiO₂nanoheterostructured composite exhibits enhanced photocatalytic activity.The surface photovoltage spectroscopy results show that the enhanced photocatalyticactivity is also attributed to its effectively-contacted between AgBr and TiO₂, andeffective capture of photogenerated holes of Br-.This study has provided some reference methods and ideas for designing andsynthesizing high performance TiO₂based nanoheterostructured photocatalysts.